The present invention relates to the field of pressure sensors and the field of fabricating pressure sensors. The present invention also relates to the field of integrating pressure sensors with other devices and systems.
Conventional pressure-sensors are used in a wide variety of applications to monitor or control pressure in devices or systems where maintaining a particular pressure is important. However, conventional pressure sensors are relatively large.
Consequently, conventional pressure sensors are not easily integrated with other devices. The conventional pressure sensor has a minimum footprint that makes such sensors difficult to incorporate in, for example, microelectronic devices. Moreover, conventional pressure sensors are difficult to integrate with microelectromechanical systems (MEMS), i.e., mechanical structures including moving parts with microelectronics.
According to one embodiment of the present invention, a pressure sensor may include a first membrane that flexes in response to pressure, a reference cavity covered by the first membrane where the reference cavity contains a vacuum and a second membrane, adjacent to the first membrane and not within the reference cavity, the first and second membranes forming a capacitor having a capacitance that varies in accordance with the flexing of the first membrane and the pressure.